1. Field of the Invention
The present invention relates to a corrugate tube and a harness structure using the same that is arranged in a vehicle body or used for an electric power-supplying device to a sliding door or a sliding seat.
2. Description of the Related Art
FIG. 6 shows an embodiment of a conventional harness exterior component 61. FIG. 7 shows an embodiment of a harness structure using the harness exterior component 61. (See Japanese unexamined utility model specification No. H04-62244)
As shown in FIG. 6, the harness exterior component 61 is so-called “cable bare” and formed by a plurality of rectangular tubular pieces 62 made of synthetic resin, of which shafts 63 and holes 64 are mutually connected and extended like a caterpillar. The harness exterior component 61 is bendable in directions of the shafts 63 and unbendable in axis directions of the shafts 63.
As shown in FIG. 7, a wiring harness 65 having a plurality of insulator-coated electric wires is inserted into the harness exterior component 61. The wiring harness 65 is extracted from both edges of the harness exterior component 61 and connected to a battery and a load respectively. The harness exterior component 61 is folded in a U-shape and arranged on both upper and lower parts in parallel in an interior of a case 66.
One edge 65a of the harness exterior component 61 is fixed on the upper part of the case 66 and connected to a wiring harness of a vehicle body with a connector. The other edge of the harness exterior component 61 is movable in the case 66 and the wiring harness thereof is connected to a wiring harness of a seat side through a cover 67 of the case 66.
As shown in FIG. 7, as the seat 68 slides, the other end 65a of the wiring harness 65 is shifted back and forth, and the harness exterior component 61 is expanded or contracted. Because the harness exterior component 61 is not bendable in the axis directions of the shafts 63 (FIG. 6), the harness exterior component 61 is smoothly expanded or contracted only back and forth.
FIGS. 8 and 9 show a corrugate tube 71 made of synthetic resin as an embodiment of another conventional harness exterior component (See Japanese published patent application No. H10-148279).
Generally, the corrugate tube 71 is a flexible tube formed by arranging alternating ridges 72 and grooves 73. The corrugate tube 71 is formed by decentered ridges 72 and grooves 73. One side 72a of the ridge 72 is projected longer in a radial direction, while the opposed side 72b of the ridge 72 is projected shorter in the radial direction thereof.
The wiring harness having the coated wires is inserted into the corrugate tube 71 so that the wiring harness is protected from outer interference, rainwater, dust, and the like. The wiring harness is, for example, led out from both edges and connected to the battery and the load respectively.
As shown in FIG. 9A, the corrugate tube 71 is curved in a smaller radius R1 in which the shorter projections 72b are inside thereof. As shown in FIG. 9B, the corrugate tube 71 is curved in a larger radius R2 in which the longer projections 72a are inside thereof. Thus, the corrugate tube 71 can be bendable corresponding to a bending radius R of a vehicle body or the like so that the corrugate tube 71 is prevented from being rattled.
The corrugate tube 71 is made of synthetic resin and has a weak rigidity. However, the corrugate tube 71 may be formed by flexible ridges and grooves of waterproofed grommets made of synthetic rubber (See Japanese published patent application No. H10-148279).
However, for the harness exterior component 61, a process for connecting a plurality of pieces 62 is required. Therefore, the conventional wiring harness costs high. Further, the pieces 62 should be thick. Therefore, the conventional wiring harness is not suitable for a light-weighted wiring harness.
The conventional wiring harness having the corrugate tube 71 formed by resin molding as shown in FIG. 8 can be formed lighter and cost lower than the wiring harness having the harness exterior component 61 as shown in FIG. 6. However, when expanding and contracting the corrugate tube 71, the corrugate tube 71 may roll or snake. Therefore, the corrugate tube 71 may interfere with the case 66 and durability of the wires inside the corrugate tube 71 may be reduced.
Accordingly, an object of the present invention is to provide a corrugate tube having flexibility in a direction to be bent, and rigidity in a direction not to be bent and a harness structure using the corrugate tube.